[PATCH] libata: fix ata_device_add() error path

In the error path, ata_device_add()

* dereferences null host_set->ports[] element.
* calls scsi_remove_host() on not-yet-added shost.

This patch fixes both bugs.  The first problem was spotted and initial
patch submitted by Dave Jones <davej@redhat.com>.  The second problem
was mentioned and fixed by Jeff Garzik <jgarzik@pobox.com> in a larger
cleanup patch.

Cc: Dave Jones <davej@redhat.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 509b048..16fc2dd 100644 (file)
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5511,10 +5511,10 @@ int ata_device_add(const struct ata_probe_ent *ent)
 err_out:
        for (i = 0; i < count; i++) {
                struct ata_port *ap = host_set->ports[i];
-
-               scsi_remove_host(ap->host);
-               ap->ops->port_stop(ap);
-               scsi_host_put(ap->host);
+               if (ap) {
+                       ap->ops->port_stop(ap);
+                       scsi_host_put(ap->host);
+               }
        }
 err_free_ret:
        kfree(host_set);